- Who can get cancer?
- Consider the source
- Consider the science
- Types of human studies on cancer risk
- Studies that observe humans
- Human testing: Clinical trials
- A closer look at the evidence
- Other questions about studies on new ways to prevent cancer
- What does this mean to you?
- To learn more
- Appendix A
Types of human studies on cancer risk
Many kinds of studies can be done in humans. Cancer prevention studies may observe people doing what they always do and compare certain activities to how many of the people get cancer. This helps them to find out if cancer risk might be linked to what they do. Or the study may offer something new (a drug, method, activity, etc.) for one group of people, and then compare them to a similar group that did nothing different.
Most human studies can be classed as either studies in which people are observed (watched), or studies in which something is done (also called intervention studies).
- An observation study about cancer risk asks questions about habits and health and looks to see if there are differences in cancer risk that may be linked to these factors.
- A clinical trial on cancer risk is one in which the researchers ask healthy volunteers to do something to see if it makes a difference in their cancer risk. (This is different from a clinical study, a more general term that includes clinical trials as well as other less careful forms of research. Clinical studies can be medical reports describing a group of patients, or even one person’s medical experience.)
Last Medical Review: 09/04/2012
Last Revised: 09/04/2012